The invention discloses a four-level DC-AC converter for a DC microgrid. The four-level DC-AC converter comprises one or more bridge arm units. Each bridge arm unit comprises a T-type three-level bridge arm and two power tubes, wherein the two ends of the T-type three-level bridge arm are connected with the two power tubes respectively. When the number of the bridge arm units is more than one, the bridge arm units are connected in parallel. The four-level DC-AC converter for the DC microgrid simplifies the structure of the convertor, and reduces conduction loss.